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                   37-36-38-42-43-44
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                   34-33-35    49-45-50
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                   31-30-32    51-46-52
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                   27-26-29    53-47-54
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                   25-24-28    55-48-56-57-out
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                      23
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       4  12 14 16 18 21  22
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    1--2--5--6--7--8--9--10
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    |  3  11 13 15 17 19  20
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